package com.adopapa.nezhacloud.common;

import java.security.MessageDigest;

public class MD5Utils {
	private final static String[] hexDigits = { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };

	/**
	 * 转换字节数组为16进制字串
	 * 
	 * @param b
	 *                字节数组
	 * @return 16进制字串
	 */
	public static String byteArrayToHexString(byte[] b) {
		StringBuilder resultSb = new StringBuilder();
		for (byte aB : b) {
			resultSb.append(byteToHexString(aB));
		}
		return resultSb.toString();
	}

	/**
	 * 转换byte到16进制
	 * 
	 * @param b
	 *                要转换的byte
	 * @return 16进制格式
	 */
	private static String byteToHexString(byte b) {
		int n = b;
		if (n < 0) {
			n = 256 + n;
		}
		int d1 = n / 16;
		int d2 = n % 16;
		return hexDigits[d1] + hexDigits[d2];
	}

	/**
	 * MD5编码
	 * 
	 * @param origin
	 *                原始字符串
	 * @return 经过MD5加密之后的结果
	 */
	public static String md5Encode(String origin) {
		String resultString = null;
		try {
			resultString = origin;
			MessageDigest md = MessageDigest.getInstance("MD5");
			resultString = byteArrayToHexString(md.digest(resultString.getBytes()));
		} catch (Exception e) {
			e.printStackTrace();
		}
		return resultString;
	}

	public static void main(String[] args) {
		String source = "appid=wx895f45111dcf1cdf&body=22222&mch_id=1233225902&nonce_str=3fefdfd537b3483e8c4e9c93430099a6&notify_url=http://www.diangang.com/app/payment/notifyUrl4Wechat.do&openid=o4l_ejqMxvywHw8wUBKJFYnSVQgU&out_trade_no=5f54c1a4561b4f0eb9007f81270289b7&spbill_create_ip=127.0.0.1&total_fee=76800&trade_type=JSAPI&key=ff64ff2ad9da0459ff44bd653d2f746f";
		System.out.println(md5Encode(source));
		System.out.println(md5Encode("wabjtam.."));
	}
}